feat(pkg): Add pathfinding edge pkg to packages dir

2022-05-22 22:46:47 +02:00
parent b9dbb97374
commit 4ee7eb909a
27 changed files with 6901 additions and 0 deletions
@@ -0,0 +1,95 @@
+import { XYPosition } from '@braks/vue-flow'
+
+const gridRatio = 10
+
+/**
+ * Each bounding box is a collection of X/Y points in a graph, and we
+ * need to convert them to "occupied" cells in a 2D grid representation.
+ *
+ * The top most position of the grid (grid[0][0]) needs to be equivalent
+ * to the top most point in the graph (the graph.topLeft point).
+ *
+ * Since the top most point can have X/Y values different than zero,
+ * and each cell in a grid represents a 10x10 pixel area in the grid,
+ * there's need to be a conversion between a point in a graph to a point
+ * in the grid.
+ *
+ * We do this conversion by dividing a graph point X/Y values by 10, and
+ * "shifting" their values up or down, depending on the values of the top most
+ * point in the graph. The top most point in the graph will have the smallest
+ * values for X and Y.
+ *
+ * We avoid setting nodes in the border of the grid (x=0 or y=0), so there's
+ * always a "walkable" area around the grid.
+ */
+export const graphToGridPoint = (graphPoint: XYPosition, smallestX: number, smallestY: number): XYPosition => {
+  let x = graphPoint.x / gridRatio
+  let y = graphPoint.y / gridRatio
+
+  let referenceX = smallestX / gridRatio
+  let referenceY = smallestY / gridRatio
+
+  if (referenceX < 1) {
+    while (referenceX !== 1) {
+      referenceX++
+      x++
+    }
+  } else if (referenceX > 1) {
+    while (referenceX !== 1) {
+      referenceX--
+      x--
+    }
+  }
+
+  if (referenceY < 1) {
+    while (referenceY !== 1) {
+      referenceY++
+      y++
+    }
+  } else if (referenceY > 1) {
+    while (referenceY !== 1) {
+      referenceY--
+      y--
+    }
+  }
+
+  return { x, y }
+}
+
+/**
+ * Converts a grid point back to a graph point, using the reverse logic of
+ * graphToGridPoint.
+ */
+export const gridToGraphPoint = (gridPoint: XYPosition, smallestX: number, smallestY: number): XYPosition => {
+  let x = gridPoint.x * gridRatio
+  let y = gridPoint.y * gridRatio
+
+  let referenceX = smallestX
+  let referenceY = smallestY
+
+  if (referenceX < gridRatio) {
+    while (referenceX !== gridRatio) {
+      referenceX = referenceX + gridRatio
+      x = x - gridRatio
+    }
+  } else if (referenceX > gridRatio) {
+    while (referenceX !== gridRatio) {
+      referenceX = referenceX - gridRatio
+      x = x + gridRatio
+    }
+  }
+
+  if (referenceY < gridRatio) {
+    while (referenceY !== gridRatio) {
+      referenceY = referenceY + gridRatio
+      y = y - gridRatio
+    }
+  } else if (referenceY > gridRatio) {
+    while (referenceY !== gridRatio) {
+      referenceY = referenceY - gridRatio
+      y = y + gridRatio
+    }
+  }
+
+  return { x, y }
+}